The inclusion of particles is known to provide various materials with modified properties. For example, layered silicates, such as those found in clays, have been employed to reduce the permeability of polymer compositions, which may be used, for instance, as barrier coatings for inflatable articles such as sports balls. See, e.g., U.S. Pat. No. 6,232,389 to Feeney et al. Such particles have also been described in conjunction with the delivery of therapeutic agents from polymer-containing regions of medical articles. See U.S. Pub. No. 2005/0181014 to Richard and U.S. Pub. No. 2005/0181015 to Zhong. As another example, carbon nanotubes have been reported for use in creating thin, flexible, high strength multilayer components for medical devices such as balloons, among others. See WO 2005/115496 to Chen et al.